public class SE {
    public static void main(String[] args) {
        System.out.println("Hello World!");

        System.out.println("------------时间1------------");

        DataType.dateType();

        System.out.println("------------时间2------------");

        Operator.operator();
    }


}
class DataType {
    public static void dateType() {
        System.out.println(Integer.MAX_VALUE);
        System.out.println(Character.MIN_VALUE);

        System.out.println("------------世纪1------------");

        byte a = 10;
        byte b = 20;
        int c = a + b;
        System.out.println(c);

        System.out.println("------------世纪2------------");

        long d = 100L;//不可以小写
        System.out.println(d);

        System.out.println("------------世纪3------------");

        String e = "弑王成王";
        String f = "弑神登神";
        String g = e + "，" + f;
        System.out.println(g);

        System.out.println("------------世纪4------------");

        int h = 30;
        int i = 40;
        System.out.println("结果为：" + (h + i));//不加括号结果为：     结果为：3040

        System.out.println("------------世纪5------------");

        int j = 50;
        String k = j + " ";
        String l = String.valueOf(j);

        String m = "60";
        int n = Integer.parseInt(m);

        System.out.println(k);
        System.out.println(l);
        System.out.println(n);

        System.out.println("------------世纪6------------");
    }
}